


Insatiable

by animehead



Category: Shingeki no Kyojin | Attack on Titan
Genre: Demons, Dubious Consent, M/M, Smut
Language: English
Status: Completed
Published: 2014-01-11
Updated: 2014-01-11
Packaged: 2018-01-08 07:11:39
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,150
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1129806
Author URL: https://archiveofourown.org/users/animehead/pseuds/animehead
Summary: <blockquote class="userstuff">
              <p>Levi wants to live in the human world, and Erwin is going to make it possible for him whether he wants to or not.</p>
            </blockquote>





	Insatiable

**Author's Note:**

> Based on this amazing art by happyds on tumblr! http://happyds.tumblr.com/post/71476410072/my-anxiety-is-killing-me-so-i-just-doodled

He’s weighed his options, has attempted to plot out multiple escapes, but Erwin knows that whatever this creature is, he’s too slow to outrun it. 

Erwin thinks he may be able to outsmart him though, to trick him into sparing Erwin, but that seems futile to say the least. Judging by the way the creature occasionally sniffs the air, Erwin has come to the conclusion that he has locked onto his scent.

In other words, he’s trapped. 

“So there you are,” the creature says, green eyes glowing brilliantly against pale skin. Various strands of inky black hair fall over his forehead, resting gently against equally dark eyebrows. “Erwin Smith.”

“Who are you?” Erwin asks, blue eyes taking in the sight of the creature, lingering over his humanlike body. He watches the way creamy skin bleeds into black, a thick covering along his arms, neck, thighs, legs, and parts of its torso.

And then there are the horns. 

“Who am I?” The creature says, his head cocked to the side, observing the man in front of him. “Who do you think I am?” The creature takes a step closer to Erwin, face expressionless, except for the mischievous twinkle in his glowing eyes. “Tell me, Erwin,” he begins. “Do you think you’re solely responsible for all your good fortune in life? Did you think there wouldn’t be some type of payback?”

“I don’t know what you’re talking about,” Erwin replies. 

“No, I suppose you don’t. But that doesn’t matter. I’m here now.”

“Are you going to kill me?”

The creature stares at Erwin for a moment before smirking. “I could. Would you like that, Erwin?” He takes a step forward, but it’s with a speed so rapid that he’s in front of Erwin in an instant. 

Erwin slams back into the wall behind him, and with nothing to protect himself, he attempts to raise his hands, but the creature clutches onto his wrists with those long velveteen fingers and pins his arms down against the wall with ease. 

“Relax, Erwin,” the creature says, his grip on Erwin’s wrists tightening. “I’m not going to kill you. I need you.”

“For what?” Erwin asks. He ignores the increasing pressure in his wrists and stares at the creature. It’s unnerving, but he takes everything in. It’s terrifying the way those eyes seem to flicker, like tiny bolts of electricity, or the way heat seems to pour over him whenever the creature speaks. 

“I want to live in this world,” the creature says. “The human world. The demon world is disgusting, and you—”

“So you’re a demon?”

Erwin grunts in pain when his wrists are squeezed even tighter and the creature leans against him. 

“Don’t interrupt me, Erwin. It makes me angry and— What’s wrong with your face?” The creature releases Erwin’s wrists and raises up, pressing its claw-like fingers against Erwin’s chest. “Your skin is red. Why?”

“Y-You’re naked,” Erwin mutters. “I can see your penis.”

The creature just stares at Erwin for a moment before rolling its green eyes. “You’re very observant. Wow.”

“I couldn’t—”

“Shut up,” the creature says, huffing, hot breath blowing against Erwin’s face. It reminds him of the feeling of opening and oven and staring inside. “Anyway,” he continues. “You owe me, Erwin Smith. And you will be my key to this world.”

“How?”

“Well, obviously, I can’t walk around like this,” the creature replies, stepping back and raising up his arms, wiggling his dark fingers. So you have to help me with that.”

“And how exactly would I do that?” Erwin asks. 

“It’s simple. You’re going to fuck me.”

“Excuse me.”

The creature rolls his eyes once more and takes another step back. “Let’s not pretend that you didn’t hear me, Erwin. And while we’re at it, let’s not pretend that you don’t know what fucking is. I’ve followed you for years. I  _know_ you know what fucking is.”

“If you’ve followed me for years then you should also be fully aware that I don’t have sex with…  _people_  whose names I do not know.”

“First of all,” the creature begins, his green eyes staring up at the ceiling as if he’s growing annoyed with the conversation. “I’m not a person. I’m a demon. Secondly, I don’t want to have sex with you. I want you to  _fuck_  me.”

“What’s the difference?”

The demon actually smirks then, his teeth shockingly white and dangerous. “That’s pitiful, Erwin. Every creature knows there’s a difference between sex and fucking. I guess you’re not as intelligent as I thought you were.” 

“My sincerest apologies.”

“Sex is what you do with everyone else. Fucking is what you’ll do with me.”

“And if I decline?”

“Then I really will kill you.”

“Then I would like to request a swift death.”

The smirk on the demon’s face disappears in an instant. “You would rather die than fuck me?” He asks, sounding both angry and offended. 

“I told you, I don’t have sex with… or  _fuck_  anyone who’s name I don’t know.”

The demon glares at Erwin before moving closer to him again. “Fine,” he grits out and reaches up to yank open Erwin’s shirt, the buttons popping from their seams and falling to the floor. He tilts his head down and presses his soft, warm lips against Erwin’s chest before pulling back slightly and blowing gently on his skin. 

Erwin opens his mouth to ask what the demon is doing, but he ends up crying out instead, feeling nothing but raw heat and pain as four letters burn into his skin, lasting only a few seconds before disappearing as quickly as they appeared. 

Levi. 

“T-That’s an odd name for a demon,” Erwin says, hand reaching up to clutch at his chest. 

“Well, I’m not particularly fond of the name Erwin,” Levi replies. “Anyway, now that you know my name, we can fuck.”

“You have a tail.”

“What does that have to do with anything? It won’t get in the way.” Levi raises his tail for emphasis and purposefully smacks Erwin in the face with it. “Stop stalling.”

“I need more information,” Erwin replies. “You can’t expect me to—”

“No,” Levi growls. He walks away from Erwin, crouches down to wedge his large claw between two boxes and pulls out a tube of lubricant. “All you need is  _this_. I’ve seen you. I know.”

“How did you get that?” 

“I stole it from your bedroom and stashed it here the last time I came in search of you.” Levi smirks again, eyes glowing even brighter than before, and far more dangerous. “I’m smarter than you, Erwin. I’ve been planning this. You aren’t in this cellar by coincidence. I wanted you in here. I  _chased_  you in here. It was a game of cat and mouse and you lost. Now fuck me. Or die.”

“Very well.”

Levi smirks as he walks past Erwin and turns his back to him. He leans forward, claws bracing against the wall, ass exposed, tail swishing side to side. He waits impatiently for Erwin to step up behind him, listens carefully for the sound of his clothing being removed. 

His face doesn’t show it, but Levi is thrilled. He’s followed Erwin for so long, watched him have sex with so many people. He knows Erwin will be perfect for him, will always be able to keep him satisfied, but more importantly, Erwin will make sure that Levi has a guaranteed spot in the human world. 

Levi moans deep in his throat when Erwin slides inside of him. He’s big and hard and it feels like Levi is being split in half, violated by Erwin’s cock. He has to resist the urge to close his eyes. He wants to see the process as it’s taking place, doesn’t want to miss it just because it feels good having Erwin’s dick inside of him. 

Erwin doesn’t ask him if he needs time to adjust before he pulls back and slams inside of him. 

Levi has to brace himself more securely against the wall to prevent falling completely against it, but that’s fine. He’s moaning now, groaning at the pleasure of having Erwin inside of him. Levi keeps an eye on his hands, watching with pure delight as black bleeds to gray, skin lightning, becoming more realistically human. With each hard thrust, he begins to look more and more like a human and he’s pleased. 

Until it becomes too much. 

“Erwin,” Levi gasps, fingers attempting to claw at the wall to escape from the powerful thrusts behind him. He tries to run away, to give himself a bit of relief, but Erwin won’t let him. Levi still has his tail, but it won’t be there for long. The worst part is that Erwin is gripping it, squeezing it tightly in his hand, preventing Levi from running. 

“What’s wrong, Levi?” Erwin asks, his breath cool on Levi’s hot skin. “Is it too much for you?” He asks with a chuckle, before yanking harder on Levi’s tail and slamming him backward. 

“Erwin!”

Erwin shifts his hips and releases Levi’s tail to opt for gripping his hips instead. He slams into Levi repeatedly, relishing in his shouts and whimpers. He feels Levi’s legs buckle from the force of his thrusts, but Erwin just grips his hips tighter and forces him to keep taking his cock, over and over, with no signs of stopping. 

Levi screams when he cums, fingernails scraping against the wall, horns steadily decreasing in size, eyes losing their terrifying glow, settling into something far more pale, a mixture of blueish green. 

Erwin still hasn’t stopped. 

“E-Enough,” Levi stammers, hand reaching back blindly to try to still Erwin’s hips, but a hand grabs his wrist and shoves it out of the way.

“Not for me,” Erwin says, and he leans forward, forces his stiff cock even deeper inside Levi, strikes that spot that makes Levi attempt to crawl up the wall. “It’s never enough.” Erwin whispers. 

And Levi knows he’s made a horrible mistake. 

He has no energy left. Can only lie slumped against the wall as Erwin continues to fuck him mercilessly. His throat is raw from shouting, from moaning, from  _begging_  Erwin, but Erwin ignores him, chuckles when Levi’s legs wobble and he falls forward, limp cock still dripping cum in a small puddle on the floor. 

“Did you ever wonder, Levi,” Erwin begins. He’s still fucking him, but he sounds so casual, not out of breath at all. “Why there were always so many of them?” 

Levi doesn’t answer. 

He can’t.

“I don’t particularly enjoy killing them, so that’s the sacrifice I make, I suppose.” Now that Levi’s tail is gone, Erwin reaches up to grip Levi’s shoulders and continues slamming him backward. “So many of them,” Erwin murmurs. “Humans are weak, after all. Aren’t they, Levi?”

“F-Fuck… you…” Levi whimpers out, face pressed harshly against the wall as Erwin continues to pound into him. 

“I’ve been courteous, I think,” Erwin continues. “Only draining them of some of their energy and sending them on their way. But you…” Erwin slams forward and Levi cries out. “I can take as much of yours as I want. You’ll just replenish it. Won’t you,  _demon_?”

Levi doesn’t need to sleep, but he’s never wanted something so badly in his life. His eyes are so heavy. He just wants to rest, to be surrounded by nothing but darkness. 

“Wake up, Levi,” Erwin purrs, and grinds into him, and Levi’s eyes snap open. He doesn’t know how long it has been, but Erwin is still going, still pounding into him, greedily drinking up his energy, hoarding it all for himself. 

“It was a good plan,” Erwin says, hips still pounding like mad, cock abusing Levi’s ass, fingers digging into his hips hard enough to leave marks. When Levi feels like he can stand no more, Erwin finally gasps and floods Levi’s ass with thick globs of cum that spill down Levi’s weak and trembling thighs. 

Erwin is kind enough to pull out gently, and the moment he does, Levi crumples to the ground like a rag doll. 

Erwin stares at him for a moment before smiling and lowering himself to his knees. He pulls Levi against him, kisses him gently on his lips. “That was perfect,” he says, and his blue eyes twinkle in the darkness. 

“Y-You tricked me,” Levi says, voice so hoarse that it comes out only as a whisper. 

“Did I?” Erwin asks with a smile. He reaches down and slides his finger into Levi’s ass, still slick with lube and Erwin’s cum. “What a greedy, little demon.”

“Fuck you,” Levi growls weakly, too exhausted to do anything but slump heavily against Erwin’s chest. “Fucking…  _incubus_.”

Erwin smiles and presses his lips gently against Levi’s ear. “You’re a lot things, Levi,” he whispers. “But you are  _not_  smarter than me.”

And though he’s glaring, Levi silently agrees. 


End file.
